SearcharxivSearch

arXiv subjects

C. Z. Vargas

Publications and source records attributed to C. Z. Vargas.

2 recordsLinked to original sources

Constraining LTB models with JLA supernovae and BAO

In the present work we constrain three different profiles of a Lemaître-Tolman-Bondi model using supernovae type Ia and baryon acoustic oscillation data. We improve common practice in the literature by carefully calibrating the supernovae in the appropriate inhomogeneous background dynamics. In addition, we address subtle issues in order to propagate the primordial BAO scale to present epoch. The combined analysis of BAO+SNIa offers a stringent test for these models. We use two distinct parameter estimation approaches, namely, the $χ^2$ and the complete likelihood functional. It has been argued that these two approaches are not equivalent and indeed our analysis shows a specific example of their departure.

astro-ph.CO

Interacting dark energy and transient accelerated expansion

We argue that interactions in the dark sector may have a crucial impact on the cosmological dynamics. In particular, the future cosmic evolution may be very different from that predicted by the LCDM model. An example is a scenario in which the currently observed accelerated expansion is an interaction-induced transient phenomenon. We discuss such type of behavior on the basis of a two-fluid toy model.

astro-ph.CO